Fig. 2.
CSF/serum quotient diagrams for IgG, IgM and IgA (‘Reibergrams’). Individual CSF/serum ratios of IgG, IgA and IgM are plotted against CSF/serum albumin ratios. Values above the upper hyperbolic discrimination line, Qlim, indicate intrathecal synthesis of the respective immunoglobulin (Ig) class. Individual intrathecal fractions, IgIF, can be directly read by interpolation from the percentiles above Qlim (median values are given in Tables 2 and 3). Vertical dashed lines indicate the median Qlim(Alb). IgG/A/M immunoglobulin G/A/M, QIgG/A/M CSF/serum IgG/A/M ratios, QAlb CSF/serum albumin ratio